The present invention relates to an air data sensing system that utilizes one or more probes, each having at least three ports for providing the necessary input pressures for determining angle of attack, pitot pressure, static pressure, and angle of sideslip of an air vehicle. A unique pressure sensor used with the three port probe comprises a unitary diaphragm type pressure sensor that is formed on a single chip and mounted on a homogeneous single base plate to minimize extraneous effects of temperature on the sensors.
Sensing air data information utilizing external pressure sensing tubes or probes on vehicles has been known. Dual static tubes and connected pressure sensors for determining the speed, altitude and angle of attack are shown in U.S. Pat. Nos. 4,378,696 and 4,378,697.
Additionally, in recent years the emphasis on making pressure sensing probes compact and low drag has been illustrated by the devices shown in U.S. Pat. Nos. 4,836,019 and 5,331,849. Aerodynamic shaping of compact or small pressure sensing probes is shown in U.S. Pat. No. 5,319,970. Another important requirement for air vehicle sensing systems is to have redundancy so that in case one system fails, the needed air data information will be provided by the redundant system.